New tightly-integrated approach offers mobility gains, but closes the door to tinkering

Windows RT -- the branded name for Windows on ARM architecture chips -- is bad news for some Windows enthusiasts. The critical release marks the first major personal computer Windows release in which Microsoft Corp. (MSFT) has turned away from a direct-sales model, and thus in a sense marks the first time Microsoft has killed users' ability to "tinker" with their system and install their own operating system.

I. Long Live the Battery -- Or So Microsoft Claims

Writes Microsoft VP Mike Aguilo in the Building Windows blog, "PC makers will provide Windows RT PCs as integrated, end-to-end products that include hardware, firmware, and Windows RT software. Windows RT software will not be sold or distributed independent of a new Windows RT PC, just as you would expect from a consumer electronics device that relies on unique and integrated pairings of hardware and software."

In other words, your Windows laptop or tablet is about to become more like a smartphone, and less like a custom-built piece of hardware -- well, if you buy a Windows RT device, at least. No longer will you be able to buy and install the operating system yourself -- your device maker will do that for you.

But for most consumers that should be a good thing. Among the benefits of its new tightly-integrated approach, Microsoft is claiming to offer up to 13 hours of HD video playback (at 60 frames per second) with a 42 watt-hour battery powering a Windows RT notebook and 10.1" screen.

Windows RT devices like the Surface by Microsoft will offer up to 13 hours of HD video playback.
[Image Source: Microsoft]

To put that in context, an 11-inch MacBook Air (35 watt-hour) from Apple, Inc. (AAPL) gets around 4-5 hours [source] of battery life. Or alternatively, Microsoft's partners can now vie with Apple, whose iPad (third generation) offers 11-hours of HD video playback [source]. Microsoft estimates up to 409 hours of standby life for its RT devices.

Of course, those are Microsoft's numbers, so take them with a grain of salt.

On the dimensions side, Microsoft promises tablets and ARM laptops as thin as 8.3 mm (roughly 12 percent thinner than the iPad), weighing as little as 520 grams (about 20 percent lighter than the iPad).

In April, the Windows Store only had 99 Metro apps [source]. By August that number has risen to 450 apps [source]. Of these, Microsoft promises "over 90%" support Windows RT, meaning there's already a few hundred compatible apps. That's still a far cry from the hundreds of thousands of apps in Apple's App Store or in Google Inc.'s (GOOG) Android Play store. But you have to start somewhere, as they say.

And then there's Microsoft's own Surface tablet/laptop hybrid, which will first launch on October 26 as an RT device. Surface uses a Tegra 3 system-on-a-chip (SoC) from NVIDIA Corp. (NVDA).

But other RT devices will also use chips from ARM Holdings plc. (LON:ARM) licensees Qualcomm, Inc. (QCOM) (makers of the Snapdragon 4) and Texas Instruments Inc. (TXN) (makers of the OMAP 4 SoC series). Noticably absent was any mention of Samsung's proprietary Exynos series or Marvell Technology Group Ltd. (FRA:MVL). It's unclear whether these ARM chipmakers will be privvy to the RT party.

Many questions -- most notably what independent benchmarks show -- remain, but at present it's clear that Microsoft is gunning for aggressive battery life and form factors with Windows RT. It is also clear that it plans to have multiple RT devices ready for the holiday season.

That should make for an intriguing battle with Apple, who will be on somewhat unfamiliar territory of being unable to sue its foe, due to their cross-licensing pact. Between that legal immunity and Microsoft's ambitious spec push, Windows RT could gain ground in the tablet space, an arena where Google's Android has largely failed (unless you count the quasi-Android Amazon.com, Inc. (AMZN) Kindle Fire).